I really want to know how to make them bigger
On my own insteasd of surgery
You can't. I'm a 36 A, and that's even after having a child. If you look at my pictures though, you would never guess my boobs are that small. Here's some tricks:
-Wear push up bras
-Gel inserts that go in your bra - they make you 1-2 cup sizes bigger and give you cleavage
-Use bronzer in between your breast - it makes shadows and gives the illusion of cleavage
-Low cut tops - they look amazing on small cheasted girls!
The female body can continue development, into your mid 20s. You've still got another 5-8 years of growing to do. Maybe by then, they'll be bigger. If not, then instead, by then you might not be as self-conscious about them.
drink a lot of milk. all day, everyday.